Actually it looks as though the guy on the ground jumped up and pulled the cable the helicopter was lowering forcing it to go into the main rotor. Watch this in slow motion and you can see how lucky everyone one and the ride the pilot had on the way down.

Why the "no"? The cable was pulled in when the guy on the ground yanked it, removing any slack that it had, and that put it within reach of the rotors. It's even stated in the video description. You're both right.

Didn't catch that the first time--at around 1:43, you can see a guy (only one NOT in a high viability vest!) jump up and grab the cable causing it to whip into the rotors... Look between middle and guy on the right of the three guys standing still in the center of the shot and you can see him jump...

The (former) EMT in me was saying that, unless there was a clear risk of fire, they shouldn't have extracted him until help arrived... Even after removing him, placing him in a folding chair (that almost folded up just before he sat down, was not the wisest action (then again, looking at what happened, it is clear that no one was really thinking clearly that day anyway...).

A) they should've used a truck crane (no reason to use a helicopter). B) the lifting cable was way too short to permit, in the event of, project abort and emergency landing. The copter could never safely descend and land, after tower section erected, with the cable slack looping below safely clear of the main rotor. Pilot, who never should've been there, didn't give himself an out. The pilot's life and safety (as for all around) depended on the copter's latch release that wasn't cooperating that day as planned.

For what it is worth, the NTSB DIDN'T investigate. Lots of countries, even small ones like New Zealand, have their own, well-qualified and competent agencies too. The report on this crash can be found on the website of the New Zealand Transport Accident Investigation Commission.

I wonder if a safety briefing with the pilot and ground crewmen prior to the flight may have helped. Seems that the ground crewman was completely clueless about the consequences of his actions, and I would think that a simple preflight briefing would perhaps have made a difference. A helicopter dropping into a construction site and raining down parts is not my idea of a good day. Of course I don't want to be the Monday-morning quarterback but....

WOW, I think he made a major over site in the close quarters of the entire Helicopter. Doesn't look like anyone was severely injured.... But I think the Helicopter has seen better days. Anything is rebuild-able however :)